There is increasing evidence that comprehension is affected in children with specific language impairment (SLI), especially children with a family history of language problems. Reliable measures of comprehension early in the 2nd year could identify children at risk for later delay and an eventual diagnosis of SLI. This research is the first phase in a prospective study of language development and academic achievement in children at risk for SLI. This pilot study (phase 1), explores the use of parent report and laboratory measures to assess comprehension in 60 children with a family history of language problems and a group of 60 children with no family risk factor, matched for gender and maternal education. Comprehension is assessed at 12 and 18 mo using (1) the MacArthur Communicative Development Inventory (CDI) comprehension checklist completed by parents and (2) a set of visual selection comprehension tasks that measure visual attention to two pictures before and after the child is cued with a target word. Language outcome at 24 mo is assessed using (1) the CDI production checklist completed by parents, (2) lexical diversity, MLU, and an IPSyn score obtained from a one-hour videotaped language sample, and (3) a standardized test of language development. These data will be used to test two hypotheses: (1) low comprehension scores at 12 and 18 mo will predict language delay at 24 mo, and (2) children with a family history of language problems will be more likely than matched controls to experience delays in comprehension and production throughout the second year.